Balcony solar in Germantown

800 W of panels on a south-facing balcony railing in Germantown produce about 730 kWh a year and save about $84.

Output by orientation and mounting

Yearly output with 800 W of panels and the inverter limited to 800 W.

Panels face On the railing (vertical) Tilted at 30°
East530 kWh890 kWh
South-east690 kWh1,030 kWh
South730 kWh1,090 kWh
South-west680 kWh1,030 kWh
West520 kWh880 kWh

Output by month

Railing (vertical) Tilted at 30°
Monthly output in Germantown, south-facing0100200JanFebMarAprMayJunJulAugSepOctNovDec
Show as a table
MonthRailing (vertical)Tilted at 30°
Jan77 kWh72 kWh
Feb73 kWh80 kWh
Mar71 kWh97 kWh
Apr58 kWh110 kWh
May48 kWh110 kWh
Jun40 kWh110 kWh
Jul45 kWh110 kWh
Aug53 kWh110 kWh
Sep55 kWh84 kWh
Oct68 kWh81 kWh
Nov78 kWh76 kWh
Dec62 kWh57 kWh

Savings and payback

At $0.2132 per kWh you save about $84 in the first year. A kit costing $1,300 pays back in about 15.4 years.

  • Electricity price: $0.2132 per kWh (U.S. Energy Information Administration, 2025-09..2026-08). Source
  • Assumes a constant base load of 150 W, so 54% of the output is used at home.
  • Power sent to the grid is not paid for.

Calculate with your own figures

Rules

Maryland

In effect since July 1, 2026

Up to 1,200 W of inverter output per meter.

  • Certified by UL or an equivalent nationally recognized testing laboratory. Kits of 391 W or less are exempt from listing provisions that would require rewiring.
  • You must notify the utility before connecting.

Last verified: October 31, 2026

Full rules for Maryland

Nearby cities

Data sources

  • Solar data: PVGIS-NSRDB, PVGIS 5.2, 2011–2015.
  • Electricity price: U.S. Energy Information Administration, 2025-09..2026-08.
  • Last verified: October 31, 2026
  • How we calculate